Motor-control system



Mo'rbR CONTROL SYSTEM Filed .June '7, 1923 Charles 1 D @6667,"

B9 W 0m Patented May 26, 1925.

UNITED STATES PATENT OFFICE.

CHARLES A. DRESSER, OF NEW YORK, N. Y., ASSIGNOR TO CLIN ELECTRIC MANUFAG TUBING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MOTOR-CONTROL SYSTEM.

Application filed June 7, 1923. Serial No, 643,831.

To all whom it vim-y cmwcrn:

Be it known that 1, CHARLES A. Dnnssnn, a citizen of the United States, and a resident of New York, in the county of New York and State of New York, have invent cd certain new and useful Improvements in Motor-Control Systems, of which the following is aspecification.

,The invention relates to systems for controlling the operation of electric motors that are used for driving large-printing presses and like machines, and in which a master controlling member for the motor circuit is power-actiuited under control of auxiliary switches to start and stop the printing press or other machine and increase or decrease its speed desired. Auxiliary control switches are usually in the form of push buttons located at dilt'erent stations on the press, each such station being usually provided with stop, inch, increase and decrease push-button switches for controlling the operation of the press as may be required from time to time, the increase and decrease" push buttons being-arranged to envrgize electro-responsive means which actuates the master controlling member to accelerate or decelerate the machine as long as one of these push. buttons is held down. Such switches for increasing and decreasing the speed ot'the press can be satisfactorily employed at points at or near the machine and at which the operator may observe the operation of the machine and so avoid ex cessively increasing or decreasing the speed or stopping the machine. It. is, however, sometimes desirable to control the speed of the press from a distant point and the prcscnt invention seeks to provide in connection with a control system such as outlined, a special controlling switch or push button for ell'ccting the operation of the power-actuated master controlling member together with means automatically controlled by the master member for limiting or arresting the ope 'ation initiated by the special controlling switch.

The present improvement is particularly applicable to the control system of the motor a or motors that operate large cylinder presses such as are used for printing newspapers, and with which the paper is fed in a continuous web from a roll. It is, of course, necessary at intervals to secure or paste the end of a fresh rollof paper to the web that is being'fed to the machine. It is necessary in effecting this operation to slow down the speed of the press but it is extremely desirable to avoid stopping its operation, it possible. Usually, however, the point at which fresh rolls are pasted or secured to the web is located at some distancefrom the press and often on a difi'erent fiOOlZ. Hence, it the operator in charge of this work were provided with means similar to that used at the other stations for decreasing the speed of the press, he might easily, in tltttllllpljlllg to decrease the speed, entirely stop it and thus afford considerable im-onvenience. in

accordance with the preferred arrangement of the resent intention, a special decrease centre or push-button switch is provided and is adapted to be located at the paper roll station and is actuated by the operator atthat stationwhen. he wishes to decrease the speed of the press and attach a new roll to the paper web. This switch, in accordance with the preferred lan, is arranged to close the circuit of a re ay which in turn closes the circuit of the pilot motor that actuatcs the master controlling switch member, the relay being arranged to close the circuit of the pilot motor for reverse operation and maintain the circuit closed so that the speed of the press is decreased until the circuit of the relay is opened. Means are also pro vided for opening the circuit of the relax when the master controlling switch is moved back to a predetermined point and the speed oi?v the press has been reduced to a predetermined amount. operator at the roll station can decelerate the press but he cannot reduce its speed be low'a predetermined amount or stop the press. Preferably also, an adjustable switch device is provided at the master controlling station for variably predetermining the speed to which the press will be decelcrated when the special decrease switch at the paper roll station is operated.

The accompanying drawing diagrai'mnati Cally illustrates the motor-control system with the preferred arrangement of the pres ent improvement applied thereto.

In the arrangement shown, a master controlling switch (a is located at the main station A and serves to control the circuits oi a large motor M and a small motor in, the small motor being arranged to operate the press or other like machine at low speeds With this arrangement th llni and the large motor at higher speeds. The master controlling member a is actuated by a ilot motor I having oppositely wound series field coils 10 and 11, so that by clos ing'a circuitthrough the pilot motor and through one or the other of the field coils, the master switch a can be moved forward or back to increase or decrease the speed of the press. The .circuits'of the pilot motor are controlled by auxiliary increase and decrease push-button switches located at one or more auxiliary stations B, such stations being usually arranged at different points adjacent the press. Each of these stations is also preferably provided as shown with stop, run-safe and inch push-button switches. Another auxiliary station C adapted to be located at the roll station and at which point new rolls of paper are attached to the web that is fed to the press, is provided with a special decrease push-button switch pThe stop push buttons have normally engaged contacts; the inch, increase, decrease, and special decrease buttons have normally oJen contacts, and the run-safe are provi ed with contacts which are closed when the run button is depressed and open when the safe button is depressed.

The master controlling station is pro- -vided, as shown, with a line switch 12 which connects the mains 13 to the positive and negative supply conductors 14 and 15. This station is also provided with electro-magnetic starting switches 16 and 17 for the p small and large motor respectively. A. novoltage relay 18 and a relay 19 controlled by the special decrease push button are also located at the master controlling station.

In its initial or off position at the end of its movement in clockwise direction, the master controlling switch a engages a contact 20 and an insulated brush holder 21 on the master switch electrically connects a contact 22 to a contact bar 23. In this position a circuit is closed from the positive conductor 14 by a conductor 24, the switch arm a, contact 20, conductors 25 and 26, through the normally closed contacts of the stop push buttons in series, thence by a conductor 27, contacts 22, 21 and 23, and by a conductor 28 through the coil of the no-voltage relay 18 and thence by a conductor 29 td the negative main conductor 15. The no-voltage relay is thus energized to open a set-of normally engaged contacts 30 and close two sets of normally open contacts 31 and 82. A circuit is then closed from the positive main conductor 14 through the contacts 32 to conductor 26, thence through the contacts of the stop push buttons in series to conductor 27, thence by a conductor 33 through the contacts 31 and coil of the no-voltage relay 18 to the tacts 20 and 22 of the master controlling switch and the relay remains energized during the movement of the master switch.

The relay contacts 31 and 32 also connect the conductors 26, 27 and 28 and the contact bar 23 of the master switch to the positive main conductor 14. These connections are, however, broken and the no-voltage relay is deenergized when one of the auxilia control stop push buttons is operate In the initial or off position of the master switch, the press can be operated at slow speed by any one of the inch buttons provided the run buttons are depressed. In this case a'circuit is closed from conductor 27 by a conductor 34 through contacts of the run-safe switches in series, thence by a conductor 35, the contacts of the depressed inchbutton to a conductor 36 and through the energizing coil of the starting switch 16 of the small motor to the return conductor 29. The operation of the switch 16 will close a circuit from the positive conductor 14 by the conductor 24 through a resistance 37, and thence by a conductor 38 through the contacts of the switch I 16 and the armature of the small motor tothe negative conductor 15. The press will then start and operate at slow speed, with the entire resistance 37 in the armature circuit of the small motor m, until the deressed inch button is released. It is noted that the circuit is always closed through the shunt field winding 39 of the small motor. a

The master switch can be shifted in counter-clockwise direction from any position by depressing one of the increase buttons to close a,circuit from conductor 35, through the contacts of the depressed push button to a conductor 40, through the field winding 10 and armature of the pilot motor I, and thence through a resistance 41 and conductor 42 to the negative supply conductor 15.- The pilot motor will then operate to move the master controlling switch a in counter-clockwise direction so long as the increase button is held depressed, or until the master controlling switch a reaches the end of its path of movement in this direction and opens a pair of normally engaged contacts'43 interposed in the conductor 40. As the master switch a. moves in counterclockwise direction from its initial or oil position, the insulated brush holder 21 thereon successively connects the contact bar 25 out diflerent port-ions of the armature resistance '37 of the small motor, and then cooperates with aseries of contacts 51 and a contact bar 52 t0 successively energize the circults of a serles of electro-magnetic switches 53 at the main station and which short circuit sections of the armature resistance 49 of the large motor M.. The master switch also cooperates with a contact bar 54; and a series of contacts 55 which are connected to the sections of a resistance 56 and by a conductor 57 to the shunt field winding 58 of the large motor. The counter-clockwise movement of the master switch thus serves to accelerate the press. v

It is noted that the inch and increase buttons will not serve to operate the press or increase its speed unless all of the run buttons are depressed. However, whether or not the run buttons are depressed, the master controlling switch can be moved in clockwise direction to reduce the s eed by actuating one of the decrease uttons. lVhen'this occurs, a circuit is closedfrom the conductor 26 by a conductor 59 to the contacts of the depressed button, thence by a conductor 60 through the field winding 11 and the pilot motor; The latter is thus operated in reverse direction to move the switch arm a clockwise and reduce the speed of the press as long as the operated decrease button is held down, or until the master switch 1 reaches its initial or off position and opens a pair of normally engaged cbntacts 61 interposed in the conductor 60. At any time the operation of the machine may be arrested by pressing one of the stop buttons to open the circuit of the no-voltage relay 18 and of the starting: switches 16 or 17 thus cutting oil the supply of current to either the large or the small motor, whichever is in operation. lVhen this occurs the contacts 30 of the relay 18 are engaged and close a circuit from the positive main 14, through the conductors 62 and 60 and'through the field winding 11 and pilot motor P, so as to move the master switch a, in clockwise direction back to its off position. Relay 18 cannot again be energized to prepare the controlling circuit for operation until after the master switch has returned to its initial or off position. I v

If the special decrease push button is depressed when the motor is running above a predetermined speed, a circuit is closed from conductor 59 through the contacts of this switch, thence by a conductor 63 through the coil of the relay 19, then through a resistance 64 to the return main conductor 15, so that the relay is energized to close two sets of normally open contacts 65 and 66. The contacts 66 are interposed in a conductor 67 around the contacts of the special decrease push button, so that a holding circuit is completed, when the relay 19 is thus operated, and which maintains the relay in operating condition after the special decrease push button is released. The contacts 65 complete a circuit from the'conductor 63 throu h a conductor 68 to the conductor '60, and thence through the field winding 11 and pilbt motor P, and the latter operates to move the master switch a in clockwise direction and decrease the speed of the press.

The amount of decrease, however, is lllllited by closing a shunt circuit around the coil of the relay 19 when the master switch (1 reaches a predetermined point. This shunt circuit is controlled by a series of contacts 69 which are arranged to be successively engaged by the master switch a and which are connected respectively to a series of contacts 7 0, one or more of which may be engaged by an adjustable switch deviceor quadrant 71, this quadrant being also connected by a conductor 72 to the return conductor from the coil or relay 19. Thus, if it is assumed that the master switch a is in the position shown in the drawing and the adjustable switch device 71 is set as illustrated, the operation of the special decrease button will energize relay 19 and the decreasing operating circuit of the pilot motor P, as described, to move the master switch a in clockwise direction and decrease the speed of the press until the master switch reaches the central contact 69 and closes a short circuit from the main conductor 14, by conductor 24, switch arm a, center contact 69, corresponding contact 70, switch device I1, conductor 72, to the return conductor from the coil of relay 19. The latter is then deenergized to open its circuit and the circuit of the pilot motor and arrest the decelerating movement of the master switch. In this way the decrease in the operating speed which can be efi'ected by the special decrease button at the paper roll station is automatically limited and the stopping of the press is avoided. The speed to which the operation of the press can thus be reduced may be variably predetermined by adjusting the switch device 71 at the master station, it being desirable to prevent deceleration to a speed lower than is necessary.

It is noted that the contacts 69 extend in a series adjacent the ofi position of the master switch and correspond to a number of adjacent low speed operating positions of the master switch. It is also noted that the adjustable switch device 71, the movement to be electrically connected to one or a number of adjacent contacts 69 next to the off position of the master switch, and when the latter is in engagement with any such contact, the operation of the special decrease push button will have no effect.

Obviously an arrangement similar to that controlled by the special decrease and master switches could be employed for increasing the motor speed to a predetermined limit. Obviously too, the improvement could be applied to various motor-control systems and changes made in the details set forth without departure from the essentials of the invention as defined in the claims.

I claim as my invention:

1. In a motor-control system, the combination with a power-actuatedcontrolling member for the motor circuit and a series of switches for controlling the operation of said member, of means controlled by said member, when one of said switches is operated, for automatically arresting said member at a predetermined point intermediate the ends of its path of travel.

2. In a. motor-control'systcm the combination with a power-actuated controlling member for the motor circuit and a series of switches for controlling the operation of said member, of means controlled by said member, when one of said switches is operated, for automatically arresting said member at a predetermined point intermediate the ends of its path of travel and an adjustable derice for variably predetermining the point at which the controlling member is so arrested.

3. In a motor-control system, the combination with a master controlling member for the motor circuit and electro-responsive actuating means for said member, of manually operable increase and decrease switches controlling the operation of said actuating means, and means controlled by said master controlling member when in or moved to any one of a number of predetermined operating positions for preventing or limiting the operation eli'ccted by a special one of said controlling switches.

4. In a motor-control system, the combination. with a motor, a master controlling member therefor and elcctro-responsive means for actuating said member in opposite directions to accelerate and decelerate the. motor, of a series of push-button switches for controlling said actuating means, a-holding relay controlled by one of said switches, and means controlled by said member for disabling said holding relay.

5. In a motor-control system, the combination with a motor, a nnister-controlling member therefor and electro-responsive means for actuating said member in opposite directions to accelerate and decelerate the motor, of a series of push-button justable switch device and means for deenergizing said relay controlled by the movement of said master member to a point determined by the setting of said adjustable switch device.

6. In a motor-control system, the combination with a motor, a master controlling member therefor and electro-responsive means for actuating said member in opposite directions to accele'ate and decelerate the motor, of a series of push-button switches for controlling said actuating means, and means automatically controlled by the movement of said master switch member to a predetermined point intermediate the ends of its path of travel for limiting the operation efiected by a special one of said push-button switches.

7. In a motor-control system, the combination with a motor, a master controlling member therefor and electro-responsivc means .for actuating said member in opposite directions to accelerate and dccelerate the motor, of a series of push-button switches for controlling said actuating means, an adjustable switch device and a series of contacts controlled by said master switch member for automatically and variably limiting the operation ell'ected by a special one of said push button switches.

8. In a motor-control system, the combination with a master controlling member and an actuating pilot motor therefor, of increase and decrease push-button switches for controlling the circuit of said pilot motor, a holding relay energized by a special one of said switches, and means controlled by the movement of said master controlling member to a predetermined point intermediate the ends of its path of movement for deenergizing said. relay.

9. In a motor-control system, the combination with a master controlling member and an actuating pilot motor therefor, oi incrcase and decrease push-button switches for controlling the circuitof said pilot motor, a holding relay energized by a special one of said switches, and means controlled by said master member for short circuiting said relay.

10. In a motor-control system, the combination with a master controlling member and an actuating pilot motor therefor, of increase or decrease push-button switches for controlling the circuit of said pilot motor, a holding relay energized by a special one of said switches, an adjustable switch device and a series of contacts cooperating therewith and with said master controlling member for short circuiting said relay at a point on the path of travel of said member determined by the setting of said adjustable switch device.

11. In a motor-control system, the combination with a master controlling member, a ilot motor for actuating said member an auxiliary switch means for controlling said pilot motor, of a special auxiliary switch for controlling said pilot motor to thereby move said master controlling member in decelerating direction, and means controlled by the movement of said member to'one of its operating positions for limiting the operation effected by said special switch.

12. In a motor-control system, the combination with a-master controlling member, a pilot motor for actuating said member and auxiliary switchmeans for controlling said pilot motor, of a relay for energizing and maintaining the circuit of said pilot'motor to move said master controlling member'in one direction,-a special auxiliary push-button switch for operating said relay and means controlled by the movement of said master member to one of its operating positions for disabling said relay.

13. In a motor-control system, the combination with a master controlling member, a pilot motor for actuating said member and auxiliary switch means for controlling said pilot motor, of a special decrease switch for controlling said pilot motor and thereby move said master controlling member in de 'celera'ting direction, and meamrcontrolled by said master member in any of its positions between its 01f position and a predetermined operating position for disabling said ecial decrease switch.

14. n a motor-control system, the combination with a master controlling member, a pilot motor .for actuating said member and auxiliary switch means for controlling said pilot motor, of a. holding relay for closing and maintaining'the circuit of said pilot motor to thereby move said master controlling member in deceleratin Y directiom-a special decrease switch or energizin said relay, and means controlled by sai master member in a predetermined number of its operating positions for deenergizing said relay. i

15. In a motor-control system, the combination with a master controlling member,

a pilot motor for actuating said member and auxiliary switch means for controlhn said pilot motor, of a holding relay for c osing and maintaining the circuit of said pilot motor to thereby move said master controlling member toward its off position, a special decrease push-button switch for energizin said holding relay, and means controlle by the decelerating movement of said member to a predetermined operating position for deenergizing said relay.

16. In a motor-control system, the combination with a master controlling member, a pilot motor for actuating said member and auxiliary switch means for controlling said pilot motor, of a holding relay for closing and maintaining the circuit of said pilot motor to thereby move said master controlling member toward its off position, a special decrease switch for energizing said relay, means controlled by the decelerating movement of said member to a predetermined operating position for de-energizing said relay, and an adjustable switch device for selecting such operating position.

17. In a motor-control system, the combination with a master controlling member for the motor circuit and electro-responsive actuating means for said member, of a manually'operable switch controlling said actuat-ing means to thereby effect the decelerating movement of said member, and means controlled by said master member when in or moved to certain of its operating positions adjacent its ozi" position for preventing or limiting the operation eiiected by said controlling switch.

18. In a motor-control system, the combination with a master controlling member for the motor circuit and electro-responsive actuating means for said member, of a manually operable switch controlling said actuating means to thereby eii'ect the decelerating movement of said member, means controlled by said master member when in or moved to certain oi. its operating positions adjacent its off position for preventing or limiting the operation eil'ected by said controlling switch, and an adjustable switch device for predetermining saidoperating position.

19. In a motor-control system, the combination with a master control-ling member and a pilot motor for actuating said member, of a manually operable switch for controlling said pilot motor to thereby move said master controlling member in decelerat ing direction, and means controlled by said master member when in or moved to certain of its operating positions, adjacent its oii' position for disabling said controlling switch.

20. In a motor-control system, the combination with a master controlling member and a pilot motor for actuating said member, of a manually operable switch for controlling said pilot motor to thereby move said master controlling member in decelerating direction, means controlled by said master member when in or moved to certain of its operating positions adjacent its oil position for disabling said controlling switch, and an adjustable switch device for predetermining said operating position.

21, In a motor-control system, the combination with a master controlling member and a pilot motor for actuating same, of a relay for energizing and maintaining the cirouit of said pilot motor to thereby move said master member in decelerating direotioma push-button switch for operating said relay, and means controlled by said master member when in or moved to certain of its operating position adjacent its off position for disabling said relay.

22. In a motor-control system, the com-.

bination with a master controlling member and a pilot motor for actuating same of 9.

rela for ener 'izin and maintainin the circuit of said pilot motor to thereby move said master member in decelerating direction, a push-button switch for operating said 15 .for disabling said relay, and an adjustable switch device for predetermining said oper- 20 ating positions.

CHARLES A. DRESSER. 

